Currently, automotive fuel systems use various types of dampers to eliminate pressure pulsations that occur in fuel rails. These dampers typically consist of a flexible diaphragm exposed to the fuel rail pressure, such that the compliance of the flexible diaphragm absorbs the fuel pressure pulsations.
A problem that is not well addressed by current damper designs is the occurrence of large magnitude changes in pressure during transient engine operating conditions. This problem is more severe in fuel systems with returnless regulators. In these systems, there is an increase in fuel system pressure during rapid engine deceleration. This is due to the rapid closing of the regulator valve combined with the greatly reduced injector flow required for engine operation in this condition.